Abstract
Surface Enhanced Raman Spectroscopy (SERS) is a specific and sensitive analytic technique suitable for detection of low concentration analyte. However, the performance of SERS is highly dependent on the type of SERS substrate used. In this study, solid base SERS substrates are fabricated for detection of low concentration dengue non-structural protein 1 (NS1) in saliva. Using an n-type phosphorous dopant, microstructural porous silicon (PSi) was fabricated using direct current electrochemical method. The PSi was deposited with different sizes of silver nanoparticles (AgNP) to increase the strength of electromagnetic field on the PSi surface. Here, the structural, electrical and Raman characterization of the fabricated AgNP coated PSi are presented. FESEM images show the cross-shaped surface structure of the substrate. The I-V curve reveals that the 75nm-AgNP samples produce better electrical conductivity property than the others. It is also observed that etching longer than a threshold reduces the conductivity performance of the substrate substantially, due to increase in the surface porosity. From Raman spectrum, the silicon peak at 520cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> shows a decreasing trend in intensity for samples with 30 min of etching. Interestingly, this observation complements that reported in our previous paper, where etching time of more than 28 min is found not suitable for producing uniform structure of PSi. The consistency between the structural, conductivity and Raman intensity can be used as indicators in developing good SERS substrate for non-invasive detection of low concentration dengue NS1 protein in saliva.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.